What data could be derived/calculated from this data - currently the daily snow capture allows the calculation of accumulated snow over a period of time - for example weekly, monthly or annual. What could be done with snow depth - average over a period of time? - i.e. average snow depth in December...

CoCoRaHs and other organizations want NEW snow depth, and TOTAL depth of snow on the ground. So if I had 8" on the ground yesterday, and it snowed 4" today, I would measure and find the total depth, which would be something equal to or less than 12". NWS wants two measurements a day, 12 hours apart. Even on a day without NEW snow, the measurement usually change due to melting or compacting.

If you have the ability to DIY electronics, then there are plenty of threads on the wx forum about hacking laser (and ultrasonic) "tape" measures into snow depth measuring devices. They provide an automated method that is easier on the pocket - if not the brain.

Perhaps an Arduino connected to a downward-pointing ultrasonic sensor would work. A software library (free) converts the pulse return time to a fairly accurate distance measurement. The two devices together will cost between 10 and 20 USD.